Cold-drawn fine seamless steel pipe has the characteristics of no oxide layer on the surface and inner wall, no leakage under high pressure, high precision, high finish, no deformation in cold bending, no cracks in flaring and flattening, and the appearance has been treated with antirust treatment and so on.
Production process:
- Pipe billet preparation: choose suitable raw materials, and prepare pipe billets that meet the requirements through cutting, heating, piercing and other processes.
- Perforation: put the billet into the perforating machine, through the action of high temperature and high pressure, make the billet form a cavity inside, forming a preliminary shape of steel pipe.
- Rolling: The perforated steel pipe is rolled to make the wall thickness and outer diameter of the steel pipe reach the specified requirements through the squeezing action of the rolls.
- Pickling and Degreasing: The material is pickled to remove the oxidised skin, oil and impurities on the metal surface to ensure the cleanliness of the steel pipe surface.
- Heat treatment: Heat treatment of steel pipe after rolling, through controlling the heating temperature and time, to make the organisational structure of steel pipe reach the best state and improve its mechanical properties and corrosion resistance.
- Straightening: Straighten the steel pipe after heat treatment to eliminate the bending and twisting produced during rolling and heat treatment and ensure the straightness of the steel pipe.
- Cold drawing: Cold drawing is carried out in the low-temperature state of the steel pipe to further reduce the wall thickness of the steel pipe and improve the precision and surface quality of the steel pipe through the extrusion effect of the drawing mould.
- Finishing: The cold-drawn steel pipe is subjected to finishing treatment, including cutting, grinding, inspection and other processes, to ensure the quality and dimensional accuracy of the steel pipe.
- Testing and quality control: Test the pipe, including appearance, size, chemical composition, physical properties and other aspects of the test to ensure that its quality meets the requirements.
- Packaging and transport: Packaging and labelling of steel pipes for storage and transport